Wire guide and tension device



Sept. 18, 1962 R. C. GRAHAM WIRE GUIDE AND TENSION DEVICE Filed Aug. 26, 1960 INVENTOR.

, Raymond 6. Graham Unite States This invention relates to toroidal coil winding apparatus, and more particularly, the invention relates to a wire guide and tension device for use with toroidal winding apparatus.

There are many types of wire guides and tension devices in use today. One is the side slider which slides along the vertical leg of the generally U-shaped cross section shuttle. This type of slider has the inherent disadvantage in that it is bulky and materially increases the cross-sectional area of the shuttle limiting the wire load that may be applied to a toroidal core. Another is the hairpin type and its offspring the spider pin type, both of which slide in annular grooves machined in the opposing inside faces of the shuttle of generally U-shaped cross section. The hairpin although inexpensive and expendable uses inside annular grooves which are extremely expensive and difficult to machine in the shuttle. Also, being inside the shuttle they diminish the amount of area in the wire cavity. The spider pin suffers from the same drawbacks as the hairpin, but in addition is very expensive to manufacture.

It is the principal object of the present invention to provide a wire guide and tension device that is inexpensive to manufacture and easy to use, and which is so constructed as to eliminate the necessity of tediously machining annular grooves on opposing inside walls of a shuttle of generally U-shaped cross section.

It is another object of this invention to provide a wire guide and tension device which will not increase the cross sectional area of the shuttle.

It is another object of this invention to provide a wire guide and tension device which permits a shuttle design having an increased wire loading area.

It is still another object of this invention to provide a wire guide and tension device having high reliability and long life.

It is still another object of this invention to provide a wire guide, a tension device and a shuttle design which are interchangeable with shuttles commonly being used, both on automatic and hand guided machines.

The invention, both as to its organization and method of operation, together with other objects not specifically mentioned, will best be understood by reference to the following specification taken in connection with the accompanying drawing.

In this drawing:

FIGURE 1 is a side elevation of the shuttle, wire guide and tension device of this invention;

FIGURE 2 is an enlarged perspective view of the wire guide of this invention;

FIGURE 3 is an enlarged perspective view of the tension device of this invention;

FIGURE 4 is an enlarged section taken along line 44, of FIGURE 1.

Referring to the drawing, the components which appear in one or more of the figures are numbered the same in each of the figures, e.-g. the wire guide 4 appears in FIGS. 1-3 and is numbered the same in all of these figures.

Referring now to FIG. 1, the invention utilizes a ring shaped shuttle 1 of substantially semi-circular cross-section, as shown in FIG. 4, having the inside side walls 12 which form a U-shaped outwardly open channel, or wire cavity. Diametrically opposed annular grooves 2 atent O are machined in the outside surface of the shuttle 1, and serve as a track or guide for the wire guide 4 and the tension device 6, both of which have fingers which snap over the open channel and into the annular grooves 2 of the shuttle 1. The annular grooves 2 being machined in the outside surface of the shuttle 1 are extremely simple and inexpensive to machine in comparison to the tedious and costly job of machining the grooves in the inside side walls 12 as has been done in the prior art. In addition, since the annular [grooves 2 are machined in the outside surface of the shuttle 1 and the wire guide 4 and the tension device 6 snap over the open channel and into the annular grooves 2 rather than in grooves machined in the side walls 12 of the shuttle 1, the open channel, or wire cavity, is unobstructed, thus the wire cavity has a much larger capacity. Experience has shown that approximately thirty percent (30%) more wire may be stored in the wire cavity using the shuttle design, the wire guide and the tension device of this invention.

FIG. 2 is an enlarged view of the wire guide 4 shown in FIG. 1. The wire guide 4 is also substantially semicircular in cross-section, and preferably of the same radius as the shuttle 1. The wire guide 4 has side Walls 8 which form a substantially U-shaped outwardly open channel as does the shuttle 1. The fingers 9 on wire guide 4 are formed to snap into the diametrically opposed annular grooves 2 on the shuttle 1 to secure the wire guide 4 to the shuttle. It may be noted that a further advantage derived from this arrangement is that the cross-sectional area of the shuttle 2 is not increased. That is, since both the shuttle 1 and the wire guide 4 are substantially semi-circular in cross-section and of the same radius, as taught by this invention, the cross sectional area of the shuttle 1 is not increased because the wire guide 4 is formed in the arc of a circle completing the circular outer configuration as viewed in cross section.

Wire guide 4 is preferably constructed out of nylon, thus it is extremely abrasion resistant and will provide high reliability and long life. It is to be understood, however, that the nylon wire guide 4 could be made of other plastics of high abrasion resistance, such as Teflon. The groove 5 and the notch 6 formed in the wire guide 4 serve to guide the wire for delivery from the shuttle 1.

FIG. 3 is an enlarged view of the tension device shown in FIG. 1. The tension clip has a substantially semicircular cross-section the same as that of the shuttle 1 and the wire guide 4, and, in addition has the fingers :10 whereby it may also be clipped over the open channel and into the diametrically opposed annular grooves 2 in the shuttle 1. The tension device 6 may be formed as a metal clip, and depending upon the tension desired, usually dictated by the size of wire being wound upon the toroidal core, may be made of different metals and in various weights. Since the metal tension devices are extremely inexpensive they may be made in a wide variety of tensions so that the operator may merely try several until the correct tension is found. Futhermore, since both the wire guide 4 and the tension device 6 are separate units they are separately replaceable and considerable savings in replacement costs may be realized, when one or the other is damaged or lost. It may be noted, however, that if it is so desired the wire guide 4 and tension device 6 may be manufactured as a single unit and the majority of the advantages previously mentioned will still be available.

In the operation of the winding machine, the shuttle 1 is spread apart at the joint 3 and threaded through the toroidal core in the manner well-known to those skilled in the art. The joint is then closed forming a circular or ring shaped shuttle. The wire to be wound on the toroidal core is then loaded on the shuttle 1 into the open channel,

or wire cavity. When the shuttle loading is complete the wire guide 4 and the tension device 6 are both clipped over the open channel, or Wire cavity, and into the annular grooves 2 by means of the fingers 9 and 10, respectively.

The free end of the wire previously loaded into the wire cavity of the shuttle 1 is now threaded through the notch 7 and along the groove 5 of the wire guide 6 and secured to the toroidal core by placing several turns of the wire thereon. The shuttle 1 is now rotated in the opposite direction to wind the toroidal core, that is, in the direction opposite to the direction in which it is rotated in loading the shuttle 1. The wire is payed out by the wire guide 4 as the shuttle is rotated and the tension device 6 provides the necessary tension to keep the wire tight, the object and the necessity of which is also well-known to those skilled in the art. On completion of the winding operation, the wire guide 4 and tension device 6 may be removed simply by exerting suiticient force to release the fingers '9 and 10, respectively, from the annular grooves 2, the shuttle I spread at the joint 3 to remove the shuttle 1 from the toroidal core. The same operation may then be repeated to wind further cores.

What is claimed is:

1. For a coil winding machine of the type adapted to wind a flexible member around toroidal cores, an improvement comprising:

a ring shaped shuttle bobbin having an outer surface with a portion which, as viewed in cross-section, forms part of a circle, and also having an outwardly open channel of U-shaped cross-section formed therein in symmetrical relation to the longitudinal rnidpl-ane of said ring;

two annular grooves disposed in said outer surface of said bobbin diametrically opposed to each other in perpendicular relation to said midplane and along one and the other leg respectively of said U;

and a wire guide and tension device having arcuate ridges frictionally and slidably engaging in said annular grooves for securing said device over said channel to said bobbin, and hav ing an outer surface portion which, as viewed in cross-section, forms a substantially half circle of the same radius and center as said first-mentioned circle so that said first-mentioned and last-mentioned surface portions complement each other to form between them a circular arc of more than semi-circular length.

2. For a coil winding machine of the type adapted to wind a flexible member around toroidal cores, an improvement comprising:

a ring shaped shuttle bobbin having an outwardly open channel formed therein of U-shaped radial crosssection;

diametrically opposed annular grooves disposed in the outer surface of said bobbin;

a resilient guiding means of complementary radial cross-section having arcuate ridges slidably engaging in said annular grooves, and having a notch and a groove therein for delivering said flexible member from said bobbin;

and a tension device also of complementary radial cross-section in contact with said guiding means and having arc-uate ridges frictionally and slidably engaging in said annular grooves for providing the necessary winding tension for said guiding means.

References Cited in the file of this patent UNITED STATES PATENTS 2,192,694 Quinlan Mar. 5, 1940 2,726,817 Barrows Dec. 13, 1955 OTHER REFERENCES Nylon in Bearings and Gears, Product Engineering, July 1950, pages l02l07.

Nylon Plastic For Mechanical Parts, Plastic Bulletin, volume 12, 1950, pages 187-190. 

